Transgenic approaches for introducing exogenous DNA into genomes is useful in making genetically modified cells. Transposon-based vectors are used for germline transformation of insects. Transposon insertion usually requires only a few specific base pairs at the target locus, which are spread randomly within the genome. Thus, transposition is undirected and transgenes embed themselves in diverse chromosomal locations. Because of cis-regulatory elements and other factors, transposon-mediated insertion of transgenes also commonly experience position effects, which result in variable expression and stability. The efficiency of germline transformation using transposon-based vectors is often quite low.